The present invention relates to improvements in apparatus for wrapping discrete commodities in prefabricated blanks which are converted into envelopes that surround the confined commodities. The apparatus of the present invention can be utilized with advantage for the making of cartons which contain arrays of cigarette packs or packs containing other types of smokers' products.
It is customary to confine arrays of cigarette packs in prefabricated blanks to form so-called cartons or bundles each of which normally contains ten packs of twenty rod-shaped articles each. As a rule, or at least in the United States, the packs in a carton form two superimposed layers of five packs each, and each pack of one layer overlies exactly the adjacent pack of the other layer.
In accordance with a presently known proposal, the making of cartons which contain arrays of cigarette packs involves the accumulation of a series of arrays of packs and the transport of successive arrays along a straight path wherein a discrete blank is draped around each array. The blanks can be placed onto or in front of successive arrays prior to admission of such arrays into the path. Reference may be had to U.S. Pat. No. 2,917,887. The patented apparatus comprises folding instrumentalities which serve to fold or flex the flaps and/or tucks at the sides and/or at the front and/or rear end of the advancing blank. The advancement of blanks and associated arrays along the straight path is interrupted in response to each interruption of delivery of arrays so that the adhesive which is applied to selected portions of each blank in order to bond the overlapping parts of a folded blank to each other is allowed to dry and cannot bond when the transport of the blank along the path is resumed. Thus, the patented apparatus operates satisfactorily only as long as all components of successive cartons are delivered at the anticipated rate and at anticipated intervals but it turns out a substantial number of rejects as soon as the delivery of one or more components is interrupted.
A modified carton making and filling apparatus is disclosed in U.S. Pat. No. 3,125,841. This apparatus also employs means for treating blanks during transport along a straight path. Successive arrays are introduced into a hollow folding mandrel, and a blank of wrapping material is thereupon draped around the mandrel to resemble a U-shaped body prior to introduction of the respective array into the aforementioned straight path wherein the projecting portions of the U-shaped body are folded to complete the conversion of such body into an envelope which completely surrounds the respective array. A drawback of the just described apparatus is that it must employ several pasters to apply layers of adhesive to selected portions of successive blanks in predetermined portions of the path along which the arrays and the originally U-shaped bodies are transported in the course of the carton-forming operation. Another drawback of the just described apparatus is that it can only process certain types of blanks. Thus, the apparatus is incapable of making so-called Europacartons except by undertaking a number of substantial and expensive alterations.
Austrian Pat. No. 248,341 discloses a further carton making and filling apparatus which employs an indexible folding turret with several folding chambers. A fresh blank is inserted into an empty chamber of the turret so that it is converted into a U-shaped body before the turret is indexed to place the inserted U-shaped body into register with an array of cigarette packs which are thereupon inserted into the turret. The turret is indexed again, and the protruding parts of the U-shaped body are folded while the respective chamber of the turret advances to an ejecting station. The turret contains an internally mounted ejector in the form of a plunger which expels the finished carton by way of the inlet of the respective chamber, i.e., counter to the direction of introduction of the respective array. The apparatus of the Austrian patent exhibits the drawback that its space requirements are excessive and also that the placing of an ejector into the interior of the turret contributes to complexity, initial and maintenance cost of the apparatus. Moreover, the apparatus must be equipped with specially designed rams or like holding devices which prevent unfolding of the flaps and tucks prior to and during expulsion of a finished carton at the ejecting station. The likelihood of opening of folded-over flaps and tucks is especially pronounced at that side of the finished carton which is located at the open end of the respective chamber.